No description available.

No description available.

The performance of unheated solar buffer zones (SBZs) or sunspaces in relatively high latitudes' locations has become increasingly controversial. Conceived as simultaneously saving energy and providing amenity, the latter characteristic has provided the user with the opportunity and/or aspiration to negate the former - by heating a sunspace during winter either directly, or by opening it up as an extended heated part of the dwelling. Scotland has been host to passive solar projects promoting the use of small sunspaces where 'opening up' is a greater risk than directly heating. 'Opening-up' signals a change from 'indirect' to 'direct' solar gain with the heated volume partially extended. Within this context, this work examines the relevant aspects of a small sunspace as a passive solar technique by posing three questions from which answers are to be sought. 1. How useful and usable are the sunspaces ? 2. To what extent are occupants' interventions affecting energy saving ? 3. What is the energy 'worth' of the two sunspaces? The vehicle for this work is the CEC Solar Energy Demonstration Project at Easthall, Glasgow, where 36 thermally sub-standard flats built in the 1960s have been retrofitted with each flat having two sunspaces on opposite facades to tackle the issue of random orientation, and a common stairwell functioning as a shared thermal buffer space. The author's close acquaintanceship with a relatively large sample of occupants over a monitoring period of two years, taken in conjunction with data from questionnaires, interviews, diaries and personal observations, has enabled a substantive 'cause and effect' analysis. The findings confirm the likelihood of user intervention negating optimum performance, especially in spring and autumn, and in association with particular household types and characteristics. Nevertheless, the mean space heating load was approximately 30% lower than it would have been for the equivalent dwelling adjusted to the same internal temperature and ventilation rate, but without the front and rear sunspaces; and winter performance vindicates the role of sunspaces in providing good air quality at a relatively low running cost. The work sets aside the issue of life-cycle, pay-back analysis since, in general terms, this is dependent firstly on how much of the cost of sunspaces is written off as necessary floor area or improved amenity, and secondly on variable costs of a complementary energy-efficient package. However, on the assumption that these factors may be favourable, the work concludes with broad design recommendations based on the research findings; in particular recognising the dominance of the 'heat recovery' rather than 'solar' mode of operation of sunspaces.

Amongst the multiple and diverse meanings and functions passive constructions hold, this study considers that the primary function of passives in Japanese is to portray an event from the point of view of an affected entity. The thesis identifies three types of affectedness in Japanese passive constructions: emotive affectedness, direct / physical affectedness, and objective affectedness. Emotive affectedness, often referred to as �adversative� meaning, has drawn attention from many researchers. It has been strongly associated in the past with the syntactic category called the �indirect passive�, but is actually also observed in many instances of the �direct passive�. Direct / physical affectedness is detected mainly in the construction here referred to as the �direct sentient passive�. This meaning is common in passives in many other languages, including English. The last type � objective affectedness � is primarily associated with �non-sentient passives�, more specifically with what is here called the �plain passive�. Many previous researchers have claimed a complete and apparently transparent correlation between syntactic and semantic distinctions of the Japanese passive. The present study rejects these direct correlations. In analysing authentic data, it becomes evident that the correlation is much more subtle than has generally been recognised, and that is a matter of degree or continuum, rather than a discrete, black and white issue. To reflect this view, this study proposes separate sets of categories for syntactic and semantic distinctions. The ultimate aim of this study is to reveal how Japanese passives are actually used in real contexts. In order to achieve this aim, detailed examination of authentic written and spoken data is conducted. Some findings of the data analysis in the present study contradict previous claims, such as the finding of a large proportion of passives with a non-sentient subject and very low frequency of occurrence of indirect passives. This research also finds that, although more than half of the propositional meanings in the passive data examined are �negative�, a considerable number of passives still appear in a proposition with a neutral or positive meaning. Another prominent finding regarding propositional meaning is that it seems to be related to the degree of centrality of the passive subject to the event. With regard to the syntactic classification of passive, in particular, it is observed that the lower the degree of the centrality of the subject of the passive to the event, the greater the likelihood that the passive clause involves a negative proposition.

High Voltage Direct Current (HVDC) transmission systems continue to be an excellent asset in modern power systems, mainly for their ability to overcome the problems of AC transmission, such as the interconnection of asynchronous grids, stability of long transmission lines, and use of long cables for power transmission. In the past 20 years, Voltage Source Converter (VSC)-HVDC transmission systems were developed and installed in many projects, thereby adding more operational benefits to DC transmission option, such as high controllability, ability to supply weak networks, and reduced converter reactive power demand. Nevertheless, VSC-HVDC transmission suffers from the disadvantages of high losses and cost. In this research, a hybrid HVDC employing a Line Commutated Converter (LCC) as rectifier and a VSC as inverter is used to supply a passive network through a DC cable. The hybrid system is best suited for unidirectional power transmission scenarios, such as power transmission to islands and remote load centers, where the construction of new transmission lines is prohibitively expensive. Control modes for the rectifier and inverter are selected and implemented using Proportional Integral (PI) controllers. Special control schemes are developed for abnormal operating conditions such as starting at light load and recovering from AC network faults. The system performance under steady state and transient conditions is investigated by EMTP-RV simulations. The results show the feasibility of the hybrid system. / UOIT

Passive air sampling techniques are an attractive alternative to active air sampling because of the lower costs, simple deployment and retrieval methods, minimum training requirements, no need for power sources, etc.. Because of their advantages, passive samplers are now widely used not only for water and indoor, outdoor and workplace air analysis, but also for soil-gas sampling required for various purposes, including vapor intrusion studies, contamination mapping and remediation. A simple and cost effective permeation-type passive sampler, invented in our laboratory, was further developed and validated during this project. The sampler is based on a 1.8 mL crimp-cap gas chromatography autosampler vial equipped with a polydimethylsiloxane (PDMS) membrane and filled with a carbon based adsorbent. Apart from the low material costs of the sampler and ease of fabrication, the design allows for potential automation of the extraction and chromatographic analysis for high-throughput analysis. The use of highly non-polar PDMS reduces water uptake into the sampler and reduces early adsorbent saturation. The thermodynamic properties of PDMS result in moderately low sampling rate effects with temperature variations. Further, the use of PDMS allows for easy estimation of the uptake-rates based on the physicochemical properties of the analytes such as retention indices determined using capillary columns coated with PDMS stationary phase. In the thesis, the theoretical and practical aspects of the new design with regards to uptake kinetics modeling and the dependence of the calibration constants on temperature, humidity, linear flow velocity of air across the sampler surface, sampler geometry, sampling duration, and analyte concentrations are discussed. The permeability of polydimethylsiloxane toward various analytes, as well as thermodynamic parameters such as the energy of activation of permeation through PDMS membranes was determined. Finally, many applications of the passive samplers developed in actual field locations, vital for the field validation and future regulatory acceptance are presented. The areas of application of the samplers include indoor and outdoor air monitoring, horizontal and vertical soil-gas contamination profiling and vapour intrusion studies.

Passive air sampling techniques are an attractive alternative to active air sampling because of the lower costs, simple deployment and retrieval methods, minimum training requirements, no need for power sources, etc.. Because of their advantages, passive samplers are now widely used not only for water and indoor, outdoor and workplace air analysis, but also for soil-gas sampling required for various purposes, including vapor intrusion studies, contamination mapping and remediation. A simple and cost effective permeation-type passive sampler, invented in our laboratory, was further developed and validated during this project. The sampler is based on a 1.8 mL crimp-cap gas chromatography autosampler vial equipped with a polydimethylsiloxane (PDMS) membrane and filled with a carbon based adsorbent. Apart from the low material costs of the sampler and ease of fabrication, the design allows for potential automation of the extraction and chromatographic analysis for high-throughput analysis. The use of highly non-polar PDMS reduces water uptake into the sampler and reduces early adsorbent saturation. The thermodynamic properties of PDMS result in moderately low sampling rate effects with temperature variations. Further, the use of PDMS allows for easy estimation of the uptake-rates based on the physicochemical properties of the analytes such as retention indices determined using capillary columns coated with PDMS stationary phase. In the thesis, the theoretical and practical aspects of the new design with regards to uptake kinetics modeling and the dependence of the calibration constants on temperature, humidity, linear flow velocity of air across the sampler surface, sampler geometry, sampling duration, and analyte concentrations are discussed. The permeability of polydimethylsiloxane toward various analytes, as well as thermodynamic parameters such as the energy of activation of permeation through PDMS membranes was determined. Finally, many applications of the passive samplers developed in actual field locations, vital for the field validation and future regulatory acceptance are presented. The areas of application of the samplers include indoor and outdoor air monitoring, horizontal and vertical soil-gas contamination profiling and vapour intrusion studies.

In situ passive sampling is the use of a polymer sorbent to directly assess freely dissolved concentration (C [subscript free]) profiles within the environment. The primary focus herein is the use of passive sampling methods to detect and quantify persistent hydrophobic organic compounds (HOCs) in sediment porewater and surface water using solid phase microextraction (SPME) profilers with polydimethylsiloxane (PDMS) as the receiving phase sorbent. Contaminated sediment sites pose a unique challenge in terms of remediation and monitoring for several reasons including: the large number of past and ongoing sources, sediment stability, and the extent of contamination. Capping with a clean layer of material, an accepted remediation approach, can reduce risk by stabilizing the underlying sediments, isolating the water column, and reducing contaminant flux. Evaluating cap performance is challenging due to the long time frames associated with migration of HOCs. Additionally, the non-sorbing nature of most caps limits the usefulness of bulk solid measurements. An alternative is the use of concentrations in the interstitial space or porewater to examine contaminant migration in the sediments and cap. Traditionally, porewater concentrations are obtained through a conversion of bulk sediment concentrations using an assumed sediment-water partitioning coefficient. This assumption often leads to a misrepresentation of risk as not all organic carbon is created equal. An alternative is the use of passive sampling with polymer sorbents to estimate the freely available concentration, C [subscript free]. In this work the focus is on the use of solid phase microextraction with polydimethylsiloxane (SPME PDMS) as the sorbent. C [subscript free] is proportional to chemical activity; therefore an accurate measurement of C [subscript free] is necessary for risk assessment and determination of transport mechanisms and ultimately improved management of contaminated sediment sites. A non-equilibrium correction protocol using performance reference compounds (PRCs) was developed to enhance the accuracy of the SPME PDMS method to assess C [subscript free]. The protocol was validated through laboratory experiments and field trials. Deployment times can be reduced without sacrificing accuracy when using the PRC protocol. Furthermore, it was shown that mathematical models of diffusive and advective flux can be fit using parameters determined from PRC desorption. The SPME PDMS with PRCs method was used at three different remediated contaminated sediment sites, Chattanooga Creek, Eagle Harbor, and the West Branch of the Grand Calumet River, to illustrate its utility at evaluating performance of in situ remediation. Overall, the results from laboratory and field studies suggest that SPME PDMS is a valuable tool for evaluating performance of in situ sediment remediation. / text

Background: Data on the typical daily exposure of non-smokers to second-hand smoke (SHS) are limited. The aim of this study was to estimate the SHS exposure encountered by adults and children in Scotland and to examine the proportion of total exposure received within different microenvironments. Methods: Primary research was carried out to gather information on SHS concentrations within cars in both simulated and real-life settings. Observational work was also carried out to determine the prevalence of exposure to SHS in cars. Further work was carried out to gather information on occupational SHS exposure. Data from all of these components were combined with data from previously published sources to produce estimates of how much SHS-derived PM2.5 exposure is typically received by adults and children within different micro-environments. Results: The contribution to total SHS exposure from each micro-environment was calculated. This was carried out for a child living in: a non-smoking home; a home where only the father smokes; a home where only the mother smokes; and a home where both parents smoke. In addition to this the equivalent dose of SHS inhaled (expressed as a mass) were also calculated for each of the micro-environments. This method was also used to determine the SHS contribution of different micro-environments for adult non-smokers. Exposure calculations were carried out assuming that exposure in the home was reduced to the levels found in non-smoking homes and the contribution from the remaining micro-environments unchanged. Observations identified that 2.4% of cars carrying children exposed children to SHS and exposure intensities during smoking car journeys can be particularly high with peak exposures ranging from 55 to 886 μgm-3. Conclusion: This is the first study to estimate the SHS exposure contributions from different microenvironments encountered by children and adults in Scotland. This study indicates that encouraging behavioural change in terms of smoking in home and car micro-environments has the greatest potential to reduce non-smokers’ daily exposure to tobacco derived fine particulate matter.

Landfill leachate production is an unavoidable by-product of landfilling solid waste. Mitigation of the adverse environmental impacts of landfill leachate is required at all active and closed landfill sites. Since leachate production continues long after the landfill is closed and no longer generating revenue, management strategies including low-cost passive and naturalized landfill leachate treatment systems are ideal. The past practice of dumping solid waste into unused tracts of land has created many brownfield sites with uncontrolled discharges of leachate to the receiving environment. Belle Park in Kingston, Ontario is an example of such a site that has been reclaimed for recreational use. A seep management strategy, which included the installation of leachate extraction wells, has been implemented at the site. Passive treatment systems, a coastal fringe wetland and a phreatophyte plots, were installed to evaluate their effectiveness in conjunction with the leachate seep management. Modelling estimated that originally, the pumping wells decreased leachate discharge by 60%, and with the newer wells in 2007 the discharge was decreased by 75- 85%. In situ pilot-scale evaluations of treatments systems are required to ensure adequate treatment of the leachate. The Merrick Landfill in North Bay, Ontario currently captures leachate produced on site and is assessing the potential of a hybrid-passive landfill leachate treatment system. This design process started with bench-scale design and assessment of active pretreatment options, followed by an evaluation of passive and semi-passive treatment systems at the bench-scale (treating 2-3 L/day) at both room (24oC) and cold (2oC) ambient temperatures. The design process culminated with a pilot-scale assessment of hybrid-passive treatment systems (treating 2000 L/d). Assessment of flow in passive treatment system is usually conducted with tracer evaluations. Vertical-flow passive treatment systems with intermittent dosing of leachate for passive aeration have both saturated and unsaturated flow regions. This research shows that tracer evaluation of these types of system was insufficient to measure the clogging within the pore spaces. Therefore a time-lagged flux method was created, based on the pilot-scale hybrid passive treatment system at the Merrick Landfill. This analytical solution quantified the changes in saturated hydraulic conductivity in the treatment system cells. / Thesis (Ph.D, Civil Engineering) -- Queen's University, 2011-09-30 15:55:45.73